RS-88

RS-88

An RS-88 is fired at Stennis Space Center
Country of origin	United States
Designer	Rocketdyne
Manufacturer	Rocketdyne (1997–2005) Pratt & Whitney Rocketdyne (2005–2013) Aerojet Rocketdyne (2013–present)
Status	Active
Liquid-fuel engine
Propellant	LOX / Ethanol MMH / NTO (LAE variant)
Cycle	Gas-generator
Performance
Thrust, sea-level	220 kN (49,000 lbf) (ethanol) 176.6 kN (39,700 lbf) (hypergolic)
Used in
CST-100 Starliner

The RS-88 (Rocket System-88) is a liquid-fueled rocket engine designed and built in the United States by Rocketdyne (later Pratt & Whitney Rocketdyne and then Aerojet Rocketdyne). Originally developed for NASA's Bantam System Technology program in 1997, the RS-88 burned ethanol fuel with liquid oxygen (LOX) as the oxidizer. It offered 220 kN (49,000 lb_f) of thrust at sea level.

A hypergolic derivative of the RS-88, fueled by monomethylhydrazine and nitrogen tetroxide, was chosen as the launch escape motor for the Boeing Starliner capsule.